Internal-combustion engine



T. PRATT. INTERNAL COMBUSTION ENGINE. APPLICATION FILED JAN. 6, I92].

1 31 754 Patented Oct. 111]), 11922 T 2 SHEETS-SHEET I.

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APPLICATION mm mg. 6. I9?!- Patemted 0%. M, T1922.

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V E m m n 5 Mm Patented Dot. 1%, 1922.

THEODORE PRATT, OF GLEN COVE, NEW YORK.

INTERNAL-COMBUSTION ENGINE.

Application filed January 6, 1921.

To all whom may concern.

Be it known that I, THEODORE PRATT, a citizen of the United States, and a resident of the town of Glen Gove,county of Nassau, and State of New York, have invented certain new and useful Improvements in Internal-Combustion Engines, ofwhich the following is a specification, reference being had to the accompanying drawings.

It is the purpose of this invention to construct the piston and co-acting parts of the cylinder of an internal-combustion.engine in such manner that the engine shall be absolutely valveless and the piston positively driven at the end of each stroke. To that end the cylinder is provided with extension chambers at its opposite ends and the piston is provided with corresponding extensions, which, during its reciprocations, move plunger-like through the extensions of the cylinder. The piston is so constructed that certain gas passages are provided arranged in such manner that at each reciprocation of the piston, the fuel is compressed and transmitted from the fuel intake to the explosion chambers in which the fuel is alternately compressed and fired, so that at each reciprocation of the piston,'a propelling impulse is applied upon its opposite sides alternately, thus in a speedy, economical and desirable manner effecting the generation of power, which, through the usual instrumentalities, is conveyed to the crank shaft of the machine. The exhaust port is located at or near the longitudinal center of the cylinder and the intake ports from the piston open into the explosion chambers ofthe cylinder at or near their ends, so that at each reciprocation of the piston, the exhaust occurs at points as far as possible from the respective intakes, and since the incoming charges are under pressure, the exhaust is made positive and the scavenging of the spent products assured.

Referring to the drawings, Fig. 1 is a longitudinal sectional view; Fig. 2 is across sectional view of the central part of the piston taken on the line 2-2 of Fig. 1; Fig. 3 is a cross sectional view of the central part of the piston taken on the line 3-3 of Fig. 1; Fig. 4 is a sectional view taken on the line 4-4 of Fig. 1; Fig. 5 a longitudinal sectional View of a modified construction ofthe piston removed from the cylinder.

Serial No. 435,451.

In the drawings 1 represents the cylinder, 2 the water jacket, 3 the crank shaft, 4 the crank, 5 the crank shaft casing, 6 the piston rod, 7 the connecting rod, 8 the stufling box,

9 the intake for the fuel, 10 the exhaust, 11

the water intake, 12 the water outlet, 13, 13 the spark plugs. These parts may be of any preferred and suitable construction.

Referring now to the parts more immediately involved in this invention. I 14 is the central part of the piston which may be a forging or casting, as preferred, and which has suitably connected to its opposite sides extensions 15 and 16 respectively, and internal tubular structures 17 and 18, which mg respectively from its opposite sides, as

seen best in Fig. 1. These collar like devices guide and control the passage of the fuel from one side of the piston through it to the other side as hereinafter explained.

These collar-like parts are so formed as to flare outwardly at opposite parts of the circumference, thus producing oppositely located recesses, and in the bottom of each recess the passageways or openings 19 and 20 are located which extend through the casting 14, so that during the appropriate reciprocation of the piston the fuel will be made to pass alternately from one side to the other of the piston through the openings. 19 and 20. piston has three sets of packing 28, which may be of any preferred form. Two of them are located by the sides of the gas intake ports 24, 24. and one of them, as shown,

in an extension or skirt 25 from the extension, and on the opposite side of the piston there are two sets of packing 26. These packings may be of any preferred construction.

27 is a chamber in the cylinder below the piston (see Fig. l), enlarged when the pis-v ton is elevated, and 28 is a similar chamber in the cylinder at the opposite end from the chamber 27 The chamber 28 is shown practically closed. because of the position 11(} The central member 14, see 75 The extension 15 of the 95 of the piston. 29 is an cxplosiou chamber at one side of the piston and so is a similar explosion chamber at the opposite side of the piston. The exhaust ll) is lm'atcd' between them. 31, 31 are ports in the cylinder with which the ports m-2i, in the piston register during the movements of the piston as hereinafter described. 32, 32 a re ports in the piston similar to the ports 24, and 33 are ports in the cylinder similar to the ports 31.

The operation is as follows:

On the assumption that the parts are in the position shown in Fig. 1, the fuel enters at the intake 9 and passes through the intake port 2% into the annular chamber between the interior wall of the extension 15 and the exterior wall. of the tubular member 17 and thence through the openings 20 into the interior of the tubular member 18 and thence into theopen chamber 27 below the piston. It will be noted that as the parts are illustrated in Fig 1, the charge in the explosion chamber 29 is under compression. The spark plug 13 being now energized, the charge in chamber 29 will be exploded, and the piston,

driven downwardly to the end of its stroke, at which time the exhaust ports 10 will have been uncovered, so'that the exhaust of the charge just exploded will take place. The downward movement of the piston has compressed the fuel in the chamber. '27 and caused it to rise, and being guided and confined by the collar like parts 22 it will pass again through the openings 20 into the chamber above described between the interior wall of the extension 15 and the exterior wall of the tubular member 17, so that when the piston is in its lowest position, the port 24 being then in registration with the port 31 in the wall of the cylinder, a fresh charge will enter the explosion chamber 29, being under some pressure, and will thus act to scavenge the previous charge from the explosion chamber 29.

lVhen the piston is in its lowermost position a fresh charge enters through the intake 9 into the enlarged space 28, which has been formed above the upper end of the piston skirt 25 by the downward movementof the piston. will. pass downwardly through the interior of the tubular member 1.7 and being guided and confined by the collar like parts .21 will pass tl'irouglii the openings 19 into the annular space between the interior of the extension 16 and the exterior of the tubular member 18, so that upon the return or upward movement of the piston this new charge will be compressed in the upper part of the cylinder, and when the piston has attained its uppermost position will pass throughpol't 32 in the piston and 33 in the cylinder into the explosion chamber 30, so that upon the next or downward movement From the space 28 the fuel of the piston, the charge thus injected. into the explosion chamber 30 will be additionall y compressed, and when the piston ha s arrived at approximately its lmvermost position the spark plug 13 being energized, this charge will in turn be tired, exhausted and scavenged, with of course the appropriate action upon the pistoi'i. In this way the continued operation of the engine is secured.

In 5 I illustrate a construction which, under certain circumstances, is desirable in that the entire piston structure can be readily taken apart for repair in the event of any member developing'defects. In this figure the parts are numbered as follows:

3 1 and 35 are the extension members which are threaded as at 36 and 87 to the central casting 38, instead of being welded or brazed thereto as illustrated in Fig. 1 and the tubular members 39 and 10 respectively engage with the collar-like parts 4L1 and 42 be made of aluminum or other similar metal.-

If one part is spoiled in the making or develops defects, it can be disassembled and replaced with a perfect part, thus saving all the other suitable parts.

The construction tends to keep the fresh fuel, which is cool, equally along the sides of the extensions which warms the gas and reduces the excess temperature of the extensionsf It will be obvious tothosc who are familiar with such matters that various modifications may be made in the details of construction of the parts above described and illustrated and yet the essentials of the invention be retained. For example, the terminal. parts of the extensions 34- and 35 may be threaded to the body parts thereof, instead of welding, and in such case the central casting 38 may be castiutegral with the extensions and, and the tubular members 39 and 40 may beclamped in place'by the threading of the terminal parts. I there'- fore do not limit myself to such details.

I claim:

1. In an internal combustion engine a cylinder having an extension chamber at each end, a piston having an extension at each side adapted to reciprocate through the cylinder extensions, a tubular member tween each piston extension and each tubular member entirely surrounding the latter, alternately operating fuel passages through the center of the piston whereby the fuel may pass alternately from one side to the other of the piston, a fuel intake, fuel passages through the walls of the picton extensions adapted to engage respectively with the explosion chambers, and with the fuel intake port, means to fire the charges and means to exhaust the products of combustion In an internal combustion engine a cylinder having an extension chamber at each end, a piston having an extension at each side adapted to reciprocate through the cylinder extensions, each piston exterision having a tubular member attached at one end to the central member of the piston and at the other end to the interior wall. of the piston extension, a chamber between the wall of each piston extension and the adjacent tubular member which entirely surrounds the latter, passageways through the central member of the piston whereby fuel may pass alternately from the said chamber on one side of the piston to that on the other, an explosion chamber at each side of the piston, ports through the wall of each piston extension adapted to connect respectively with the explosion chambers and with the fuel intake, means to fire the charges in both explosion chambers and means to exhaust the products of combustion therefrom.

3. An internal combustion engine comprising a cylinder havingan extension chamber at each end of less diameter than the cylinder proper, a piston having a cen tral member or piston proper, an extension projecting from each side of the central member of less diameter than it, a tubular member in each piston extension, a chamber between the wall of each piston extension and each tubular member which entirely surrounds the latter, fuel passages through the central member of the piston, whereby the fuel may alternately pass from one side ofit to the other, and ports through the wall of each piston extension adapted to engage with the explosion chambers of the engine and with the fuel intake, means to fire the charges in each explosion chamber and means bustion.

at. An internal combustion engine comprising a cylinder having an extension chamber at each end of less diameter than the cylinder proper, a piston having a central part, extensions projecting from opposite sides of the central part of smaller diameter than it, a tubular member in each extension connecting it with the central. member at their inner ends and with the extension members at their outer ends, a fuel chamber between the walls of each extension member and the tubular member within it and which entirely surrounds the latter, passageways through the central member whereby fuel may pass alternately from one of said chambers into the other and vice versa, ports through the wall of each. piston extension adapted to engage with the explosion chambers of the cylinder, means whereby fuel may be supplied to one of said chambers, means to fire the charges in each explosion chamber and an exhaust port between the explosion chambers.

5. An internal combustion engine comprising a cylinder having an extension chamber at each end of less diameter than the cylinder proper, a piston having a central part, extensions projecting from opposite sides of the central part of smaller diameter than it and detachably attached to it, a tubular member in each extension detachably connected with the central member at one end and with the piston extensions at the opposite end, a fuel chamber between the walls of each extension member and the tubular member within it, passageways through the central member may pass alternately from one bers into the other and vice through the wall of each piston extension adapted to engage withthe explosion chambers of the cylinder, means whereby fuel may be supplied to one of said chambers, means to fire the charge in each explosion chamber and an exhaust port between the explosion chambers.

In testimony whereof I name to this specification.

THEODORE PRATF.

to exhaust the product of comof said chamversa, ports have signed my whereby fuel 

